I've got three partial boil extract batches under my belt and I'm ready to move on to all grain brewing. I'm planning 4-5 gallon batches BIAB style for now. So far, I've got a nine gallon pot, and I'm working on a fermentation chamber. I'm working on different options for heat, but my main question is around chiling. Since I'll be moving to full boils, I would like some sort of chiller to get my wort down to yeast temperature in a normal time. I've got a couple different ideas and wanted to get some thoughts from others that may have been in this spot before. I'm trying to keep cost as reasonable as I can and upgrade as I go, my monthly play money is tight.

1. Plate chiller, ~$100
Pros: Good for chilling, I should be able to gravity feed it for a while until I get a pump.
Cons: When I get to the point of a 2 or 3 vessel system, I'm going to need a separate RIMS or HERMS system to maintain mash temp or step boils, that may be in a year or two or futher down the road.

2. HERMS coil built in kettle, ~$100
Pros: I'll be able to use the coil in the future for HERMS
Cons: With the coil fixed, chilling will be slow, I'll need to spend an extra $150 on a pump to get good chilling by recirculating.

I'm not planning on immersion chiller as it seems kind of pointless as it will only chill a little better than an HERMS coil and the cost for the HERMS is similar. I'm not planning on the CFC as cost is comparable to plate chiller and has similar pros and cons.

I'm doing 5-gallon BIAB batches in a 10-gallon kettle. I ended up building a CFC, after seeing a friend of mine use his. It's not nearly as compact as a plate chiller, but I was able to build it for about $50. In addition to cooling the batch in about 10 minutes, it also aerates the wort as it falls into the fermenter. There are lots of different options, you'll be able to find something that will work with your brewing system.

My concern isn't with the pre chill, I live in Idaho so my ground water is pretty cold.

My concern is with the immersion chiller or herms coils, that the wort isn't always by the cold, I'd need to stir with a spoon or something similar, the pump was to recirculate Jamil style, pumping cooling wort back into the kettle while chilling. I'd want to use a March style pump for that. I wouldn't want to use a HF pump for something that was coming in contact with the cooling wort.

Many people with immersion coils just move the coil around in the kettle. No pump needed if you're willing to put in a little elbow grease. There's a few videos of JaDeD's ICs taking 5 gallon batches from flameout to pitching within about 5½ minutes. Here:

I was considering picking up this helix mixer that could be used in a herms coil pot loaded using a power drill. It's spec'd as polypropylene, so it's solid well past the boiling point of water. No stainless, but probably safe as long as you treat it well. Perhaps that's a little more hands-on than you wanted. But also only $7.

I would invest in a large plate chiller. This will work on a gravity fed system and is very efficient in terms of cooling to waste water usage. Duda Diesel is probably the best value. When you order, specify the fittings that are threaded for configuring and adapting to future systems. Just my 2cts worth. Here is a link to how I follow the plate chiller with an immersion chilling in line to get the wort down to lager temps.
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